A hamster that is well taken care of is usually healthy and happy. But as a hamster owner you need to be on the lookout for certain signs that can tell you if you have a sick hamster. Here are five warning signs to check for as you handle and play with your hammy.

1. Wet Bottom

When you are handling your hamster, does its bottom feel wet? This could simply indicate that your hamster just peed. But if the bottom is very wet or wet very often or if you notice matted fur down there, it could indicate that your hamster has wet tail.

This is a dangerous bacterial infection. What’s more, this is a contagious disease that can affect other hamsters. Wet tail can be cured but I advise taking your hamster to the vet immediately.

2. Diarrhea

If you look around the cage and see that your hamster is leaving wet poo everywhere, you can be pretty sure he or she has diarrhea. Diarrhea is another warning sign for wet tail. But it could be that your hamster is just eating too many vegetables or other kinds of treats.

The danger here is that diarrhea means your hamster can get dehydrated. Because the hamster is a small animal, dehydration can lead to a quick death. Check to make sure your hamster is getting enough water. You may try cutting back on fresh vegetables. But if the diarrhea continues, this may mean wet tail and a trip to the vet.

3. Red skin or bald patches

Under all that hamster fur is hamster skin. By moving the fur around you may see a potential warning sign if the hamster skin looks red in spots, has bald patches, or some kind of lump.

These hamster skin problems indicate a skin disease that will require a vet to take a closer look. One of the factors could be that you are not cleaning the hamster’s cage often enough or you are using the wrong kind of bedding material. See the article Types of Hamster Bedding Material for more information about bedding material.

4. Teeth growing too long
You know that hamsters have to keep gnawing with their teeth because their teeth are always growing. But a warning sign would be if you notice that your hamster’s teeth are beginning to grow longer than they should. Look inside your hamster’s mouth and make sure its teeth are not getting too close to its cheeks. Also look for sores inside your hamster’s mouth. If the teeth get too long they can pierce the mouth.

Gnawing on wooden toys, fresh vegetables, and treat blocks can help your hamster keep its teeth the right size. But if your hamster is getting overgrown teeth, you may have to go to a vet who can trim your hamster’s teeth.

The final warning sign is if you look inside your hamster cage and your hamster is not moving. Most times, this just means your hamster is taking a nap. But if your hamster remains in that position for a long period of time and you have trouble waking it up, he or she may be in hibernation. When a hamster goes into hibernation it breathes very slowly and is in a deep, deep sleep. The hamster may look like it’s dead. But unless your hamster is old, this may just be hibernation.

Your hamster will do this if it gets too cold inside its cage. A hamster needs a temperature of about 68 to 78° F (20 to 25 C). If it gets colder than this your hamster may go into hibernation. You will need to immediately try to start warming up your hamster in your hands. Eventually, with enough heat, your hamster can wake up.

When taking care of your hamster, you face routine health problems as well as the occasional illness and disease. Let’s first consider some of the routine health issues.

Routine Health Issues

Overgrown teeth: Hamsters are born with a pair of incisor teeth in their upper and lower jaws. The teeth continue to grow throughout a hamster’s lifetime. By gnawing on hard things they can keep their teeth from growing too long.

If the hamster’s teeth get overgrown they could cause problems such as piercing the animal’s mouth. If this happens, see a vet immediately.
You may see your hammy chewing on the metal bars of his or her cage. Some chewing on cage bars is normal. But excessive chewing can break the hamster’s teeth.

Be sure to get your hammy chew toys that allow him or her to properly gnaw their teeth. Wood toys are good, but be sure the wood is not too soft. Some people recommend dog biscuits to help hamsters keep their teeth in check.

Overgrown claws / nails: As with many other animals, hamster nails continually grow and may need to be trimmed. You can trim the claws yourself, or ask you vet to do it.

Matted fur coat: Hamsters that have long hair, such as Teddy Bear Hamsters, can get bedding stuck in their hair, causing a section of their fur to become matted. First try gently brushing your hamster’s coat. If the mat is really bad, you may have to use a small scissors and very carefully cut out the matted section of fur. Bathing your hamster is not recommended.

Hibernation: Hamsters are sensitive to temperature. Too hot and they can get heat stroke. Too cold, and the hamster can go into hibernation. This will cause your hamster’s whole body to slow down. They breathe very slowly and look like they are in a deep sleep. You might think the hamster has died.

You will need to warm up the hamster, preferably by taking him or her in your hands and gently rubbing them. Do not do this in a microwave or oven!

If you keep your hamster cage in an area where the temperature is about 68 to 78 degrees F (20 to 25 C) you should be fine. Avoid putting your hamster cage in a window or someplace where it gets direct sunlight. See the article about hamster cage location for more information.

Hamster Illness and Disease

The following are some typical hamster illnesses you should watch out for. They will typically require a trip to your vet.

Wet Tail: Wet tail is a bacterial infection. It is caused by the stress of a changing location (such as from a pet store to home) and too much handling. Look for a wet and soiled bottom area, diarrhea, a loss of appetite, and/or a bad smell. This disease is also contagious, so if one hamster gets it, other hamsters sharing a cage are likely to get it.

The disease can cause hamster death within a short time period, especially when the diarrhea is severe and leads to dehydration. Wet tail is curable, but you should take your hamster to your vet, who will probably give the hamster antibiotics.

Diarrhea: Hamsters can get diarrhea without wet tail. You may notice they still are active and have not lost their appetite, but are leaving soiled bedding all over the place. It is usually caused by the hamster overfeeding themselves with fresh vegetables. You may want to stop feeding your hamster fresh foods for a few days and see if the diarrhea clears up. Then slowly start giving the hamster fresh food again.

If the diarrhea goes on too long, the hamster could develop dehydration, which can lead to death.

Respiratory/Lung Infections: There are a number of causes of breathing problems in hamsters. Improper bedding, such as pine or cedar chips, can cause dust or small particles to get into your hamster’s lungs and cause breathing problems. Look for a slow down in hamster activity, wheezing or a hamster who is having difficulty breathing. Some hamsters may also start sneezing a lot.

Another cause of lung infections can be the aspergillis fungus. This is a fungus that can grow in the hamster’s bedding, usually where the hamster pees. Initially it can’t be seen, but then turns white and finally black. The fungus can then send spores airborne causing breathing problems for your hamster.

If you see any signs of wheezing or breathing problems, get your hamster to the vet immediately.

Skin Diseases: Skin diseases that can affect hamsters include skin infections, ringworm, mites, and allergies. Look for reddening of the skin, bald patches or hair loss, or lesions (growths) on your hamster’s skin. You may also notice your hamster scratching itself more than usual.
You will need to see your vet, who can tell you the exact skin disease and provide the appropriate treatment.
Not cleaning a cage often enough or use of poor bedding, such as pine or cedar wood chips, can contribute to your hamster’s skin disease. See the hamster bedding article for more information about bedding materials.

Abscesses: Abscesses are obvious sores or blisters on your hamster’s skin. Sometimes food will cause abscesses to occur in your hamster’s cheeks. It may look like the hamster is always storing food in his or her cheek pouch.

Abscesses need to be drained, so take your hamster to your vet if you notice one.